[src/netbsd-1-6]: src/sys/dev/scsipi Pull up revision 1.53 (requested by bouy...

[tron <tron%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/988a11d4bac2
branches:  netbsd-1-6
changeset: 529225:988a11d4bac2
user:      tron <tron%NetBSD.org@localhost>
date:      Fri Nov 01 16:40:31 2002 +0000

description:
Pull up revision 1.53 (requested by bouyer in ticket #733):
Do PIO transfers for len < 4 bytes. From Matthias Drochner in private mail.

diffstat:

 sys/dev/scsipi/atapi_wdc.c |  8 +++++---
 1 files changed, 5 insertions(+), 3 deletions(-)

diffs (30 lines):

diff -r f34356edc0d0 -r 988a11d4bac2 sys/dev/scsipi/atapi_wdc.c
--- a/sys/dev/scsipi/atapi_wdc.c        Fri Nov 01 16:37:42 2002 +0000
+++ b/sys/dev/scsipi/atapi_wdc.c        Fri Nov 01 16:40:31 2002 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: atapi_wdc.c,v 1.52 2002/05/18 14:49:55 bouyer Exp $    */
+/*     $NetBSD: atapi_wdc.c,v 1.52.2.1 2002/11/01 16:40:31 tron Exp $  */
 
 /*
  * Copyright (c) 1998, 2001 Manuel Bouyer.
@@ -32,7 +32,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: atapi_wdc.c,v 1.52 2002/05/18 14:49:55 bouyer Exp $");
+__KERNEL_RCSID(0, "$NetBSD: atapi_wdc.c,v 1.52.2.1 2002/11/01 16:40:31 tron Exp $");
 
 #ifndef WDCDEBUG
 #define WDCDEBUG
@@ -368,8 +368,10 @@
                 * 2 bytes. It's a bug to request such transfers for ATAPI
                 * but as the request can come from userland, we have to
                 * protect against it.
+                * Also some devices seems to not handle DMA xfers of less than
+                * 4 bytes.
                 */
-               if (sc_xfer->datalen & 0x01)
+               if (sc_xfer->datalen < 4 || (sc_xfer->datalen & 0x01))
                        xfer->c_flags |= C_FORCEPIO;
 
                xfer->cmd = sc_xfer;